Sequences are a handy feature in SQL server which provide an increasing, unique number. You wouldn't typically use them directly but might use them under the covers in an identity
. However from time to time they are useful when you need numbers but your primary key is a uniqueidentifier
or you need two different ways of numbering records. I've been using them to associate records in a table into groups.
1 | create SEQUENCE Seq_PermitNumber |
You can then use them like this
1 | update tblManualPayment |
This will give each record a unique permit number.